US-12622657-B2 - Assisting scapula positioning in chest X-ray imaging

US12622657B2US 12622657 B2US12622657 B2US 12622657B2US-12622657-B2

Abstract

The present invention relates to assisting scapula positioning in chest X-ray imaging. Provided is a system and related method for assisting subject positioning in chest X-ray imaging, wherein the system comprises an optical detection device ( 110 ), a user interface ( 130 ), and a processor ( 120 ), connected to the optical detection device ( 110 ) and the user interface ( 130 ). Thereby, the processor ( 120 ) is configured to receive an optical image signal of a rear view of the subject(S), determine a current positioning of a scapula of the subject(S) based on the optical image signal, wherein the current positioning of the scapula is assessed as to whether and/or to which extent it would overlap or would not overlap a lung field of the subject to be imaged and determine a feedback for positioning the subject(S) and/or its scapula based on the determined current positioning of the scapula. The user interface ( 130 ) is configured to provide the feedback for positioning the subject.

Inventors

Sven Kroenke-Hille
Daniel Bystrov
Martin Bergtholdt
Bernd Menser
JULIEN THOMAS SENEGAS

Assignees

KONINKLIJKE PHILIPS N.V.

Dates

Publication Date: 20260512
Application Date: 20221107
Priority Date: 20211116

Claims (15)

1 . A computer-implemented method for assisting subject positioning in chest X-ray imaging, comprising: receiving an optical image signal of a rear view of the subject; determining a current positioning of a scapula of the subject based on the optical image signal, wherein the current positioning of the scapula is assessed as to whether and/or to which extent it would overlap or would not overlap a lung field of the subject to be imaged; determining a feedback for positioning the subject and/or its scapula based on the determined current positioning of the scapula; and providing the feedback for positioning the subject.
2 . The method of claim 1 , wherein determining the current positioning of the scapula comprises determining an arm and/or wrist positioning of the subject being indicative for the current scapula positioning from the optical image signal.
3 . The method of claim 1 , wherein a set of landmarks on or of the subject is derived from the optical image signal to assess the current scapula positioning.
4 . The method of claim 3 , wherein a geometric relationship being indicative for the current scapula positioning is determined from the set of landmarks.
5 . The method of claim 3 , wherein a plane spanned by one or more extremities of the subject is determined from the set of landmarks, and wherein the determined plane is compared to a target value to derive the current scapula positioning therefrom.
6 . The method of claim 3 , wherein at least one angle between an arm of the subject and its torso and/or its body center and/or a detector plane of an X-ray imaging device is determined from the set of landmarks, and wherein the at least one determined angle is compared to a target value to derive the current scapula positioning therefrom.
7 . The method of claim 3 , wherein the set of landmarks is determined on both sides of the subject for both scapulae, and a symmetry and/or congruence of both sides is determined to assess the current scapula positioning.
8 . The method of claim 1 , wherein one or more contours of the subject and/or one or more surface properties of the subject are derived from at least the optical image signal to assess the current scapula positioning.
9 . The method of claim 1 , wherein the optical image signal is received from a classifier or a model trained on annotated training data, and wherein the classifier or the model determines the current scapula positioning based on at least the optical image signal.
10 . The method of claim 1 , wherein a depth information data is received from a depth channel of an optical detection device used to capture the optical image signal of the rear view of the subject.
11 . The method of claim 1 , wherein a depth information data is received directly from a 3D depth map based on at least the optical image signal.
12 . The method of claim 1 , wherein a depth information data is determined based on a stereo optical detection device used to capture the optical image signal of the rear view of the subject.
13 . The method of claim 1 , wherein the feedback comprises or forms a trigger signal configured to control and/or prevent image acquisition based on the scapula positioning.
14 . A system for assisting subject positioning in chest X-ray imaging, comprising: an optical detector; a user interface; and a processor, connected to the optical detector and the user interface, wherein the processor is configured to: receive an optical image signal of a rear view of the subject; determine a current positioning of a scapula of the subject based on the optical image signal, wherein the current positioning of the scapula is assessed as to whether and/or to which extent it would overlap or would not overlap a lung field of the subject to be imaged; and determine a feedback for positioning the subject and/or its scapula based on the determined current positioning of the scapula; wherein the user interface is configured to provide the feedback for positioning the subject.
15 . A non-transitory computer-readable medium for storing executable instructions, which cause a method for assisting subject positioning in chest X-ray imaging to be performed, the method comprising: receiving an optical image signal of a rear view of the subject; determining a current positioning of a scapula of the subject based on the optical image signal, wherein the current positioning of the scapula is assessed as to whether and/or to which extent it would overlap or would not overlap a lung field of the subject to be imaged; determining a feedback for positioning the subject and/or its scapula based on the determined current positioning of the scapula; and providing the feedback for positioning the subject.

Description

FIELD OF THE INVENTION The present invention relates to medical imaging, and in particular to a computer-implemented method for assisting subject positioning in chest X-ray imaging, to a system for assisting subject positioning in chest X-ray imaging, and to a computer program element. BACKGROUND OF THE INVENTION In medical imaging, e.g. in X-ray imaging, appropriate subject positioning can be regarded as being crucial for achieving X-ray images of diagnostic quality. In case of chest X-ray imaging, a scapula, i.e. shoulder-blade, must be rotated outside of the lung-field since otherwise relevant parts of the lung-field may be partially occluded, cover, which renders the image difficult to be read. If the scapula positioning causes occlusion of or overlap with the lung field, it may be necessary to repeat the image acquisition, which is time-consuming, causes longer occupancy of the X-ray imaging device, and results in a higher radiation dose to the patient. Thereby, the required subject's pose is rather inconvenient and not easy to be taken, so that detailed instructions by the operator are required for achieving a proper scapula positioning. Further, time-pressure and a lack of experience, can result in an inappropriate subject positioning reducing the diagnostic quality of the x-ray image. SUMMARY OF THE INVENTION There may, therefore, be a need for improved means for at least assisting positioning of a subject in a manner allowing acquiring a medical image with a desired positioning of the scapula. The object of the present invention is solved by the subject matter of the independent claims, wherein further embodiments are incorporated in the dependent claims. According to a first aspect, there is provided a computer-implemented method for assisting subject positioning in chest X-ray imaging. The method comprises receiving an optical image signal of a rear view of the subject and determining a current positioning of a scapula of the subject based on the optical image signal, wherein the current positioning of the scapula is assessed as to whether and/or to which extent it would overlap or would not overlap a lung field of the subject to be imaged. Further, the method comprises determining a feedback for positioning the subject and/or its scapula based on the determined current positioning of the scapula and providing the feedback for positioning the subject. In this way, the required subject's positioning and/or its scapula's positioning, which is rather inconvenient and not easy to be taken, can be assisted in an automatic manner by automatically determining and providing appropriate instructions to e.g. an operator, e.g. a radiographer, to achieve a good scapula positioning. Further, the above method is carried out radiation-free, since an optical image signal, e.g. from a camera or the like, is used, so that the radiation dose for the subject can be limited or even reduced. In other words, in chest imaging it is desired the shoulder blade(s) to be rotated outside of the lung-field since otherwise relevant parts of a lung field may be masked and partially occluded, wherein the above method allows to evaluate and improve the positioning of the shoulder blade(s), i.e. the scapula (e), with respect of the positioning's impact on the imaging quality. As used herein, a rear view of the subject or the optical image thereof may be understood as an image of the subject's back at the level of the chest and shoulder blades. Thereby, the optical image can be understood in distinction to an X-ray image as an image taken without radiation, wherein the optical image may be acquired by an optical detection device, such as an optical camera, a depth-resolving camera, or the like, with known relative position to the focal point of the focal point of an X-ray device, e.g. its X-ray tube, used for the actual X-ray imaging. The depth information may be understood as e.g. pixel-wise information about a distance of the subject to the optical detection device and/or the X-ray device. It may also include a depth map. For example, elevations, depressions, flattenings, etc. of the subject can be recognized from this. The feedback, which may be output graphically, e.g. via a display etc., via audio, e.g. via a loudspeaker, headphone, etc., or the like, may indicate that the positioning is already correct, at least in a sufficient manner. That is, the feedback may confirm correct positioning. However, if there is a deviation between the current positioning and a desired target positioning, the feedback may indicate how the positioning of the subject and/or scapula is to be changed to comply with the target or desired positioning, where it does not cover or overlap with a lung field of the subject to be imaged. As used herein, the optical image signal may be indicative of an outward rotation of the scapula relative to a torso and/or a center of the subject's body. Thereby, with sufficient outward rotation, good visualization of t